Pineal Germ Cell Tumor with Upgaze Palsy

Abstract

A 14-year-old boy presented with complaints of diplopia for 1 month. He had a minor head injury 1 week before the onset of diplopia. He was hit in the head with a ball, but did not report feeling any significant discomfort at that time. He began to experience double vision afterward and visited a local ophthalmologist. He was subsequently transferred to our clinic. His vision was 6/6.7 in the right and 6/6 in the left. Color vision and intraocular pressures were normal. Anterior segments were normal. Ophthalmoscopic examination showed normal fundi in both eyes (Fig. 40.1). A prism cover test revealed 1 prism diopter of left hypertropia on primary gaze and increased measurements on right gaze and left tilt. The results of a park three-step test were compatible with left trochlear nerve palsy. An extraocular movement examination showed moderate limitation of upgaze in both eyes (Fig. 40.2, Video 40.1). Visual field testing revealed enlarged blind spots in both eyes (Fig. 40.3). MRI showed a pineal tumor with cystic space, which was isointense on T1-weighted images and hyperintense on T2-weighted images. The tumor was enhanced after gadolinium injection (Fig. 40.4). Under the impression of germ cell tumor, there was subtle seeding into third ventricle noted along with associated obstructive hydrocephalus. A peripheral blood examination demonstrated increased AFP (3295 ng/mL) and β-HCG (151 mIU/mL). The patient hesitated to receive surgical biopsy, and there was subsequent loss to follow-up.